Run most of the unordered container tests (not the exception tests) on warning

level 4 on Visual C++.


[SVN r38648]

test/helpers/generators.hpp

@@ -59,7 +59,7 @@ namespace test
     inline signed char generate(signed char const*)
     {
         using namespace std;
-        return rand();
+        return static_cast<signed char>(rand());
     }
 
     inline std::string generate(std::string const*)